The twurex Shells. Rock Shells 



Mediterranean Murex is eaten by poor people along the coast, 

 though it is no delicacy. The Tyrian purple was extracted in 

 ancient times by bruising mollusks of this species in pot holes 

 in the rocks along the sea coast. 



Sub-genus HOMALOCANTHA, Morch. 



Whorls rounded; sutures deep; varices leaf-like and pro- 

 duced into fingers, dilated at the tips or spiny; canal short, curved, 

 wide, almost closed. Four Oriental species. 



The Scorpion Murex (M. scorpio, Linn.) is remarkable for 

 the finger-like, channelled fronds, flattened into broad tops, that 

 ornament the last of its five varices. The others bear stumpy, 

 straight spines. A deep and wide spiral suture separates the 

 whorls, almost cutting off connection between the body whorl 

 and the spire. The canal is wide and open. Colour, white to 

 chocolate; varices dark-coloured. Length, ij to 2^ inches. 



Habitat. — Moluccas, Philippines. 



The Windowed Murex {M. fenestratus, Chemn.) is decorated 

 with a regular lattice-work of ridges which intersect at right 

 angles, leaving square dark window-like pits. There are five or 

 six varices, bearing branched orange-yellow spines so delicate as 

 to be broken from most specimens we see. This is one of the ele- 

 gant fusiform rock shells. Length, ij to 2 inches. 



Habitat. — Philippines, Red Sea. 



Sub-genus PHYLLONOTUS, Swains. 



This group differs from Chicoreus in having numerous varices- 

 The more varices, the more chance for elaborate ornamenta- 

 tion of the shell. In this sub-genus the Murex tendency to spiny 

 outgrowths reaches its highest possibilities. The names indicate 

 how these shells bristle with close-set fronds and prickles and 

 laminations. 



The Root Murex (Af. radix, Gmel.) is almost globular with 

 short black, triangular spines set close on its ten to fifteen frondose 

 varices. The white ground colour is almost concealed by this 

 black stubble, which leaves only the top of the spire exposed. 

 It looks like some rough tuberous root. Length, 3 to 5 inches. 



Habitat. — Panama. 



The Banded Murex (M. trunculus, Linn.), the commonest 

 Mediterranean species, is modest in its pretensions. The keeled 



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